Problem 1 In how many way can 5 persons wait in line at the

Problem 1. In how many way can 5 persons wait in line at the cafeteria?
Problem 2. How many different ID cards are possible if there are 6 digits (slots) on a card and no numeral may be used more than once?e.g. This 6 digit ID is not allowed: 429468. This is because the numeral 4 was used more than once. However, this 6 digit ID is allowed: 429768.

Solution

1)
Number of ways = 5*4*3*2*1
                      =120

2)
Number of ways = 9*9*8*7*6*5
                            =136080